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Cooperative Authentication in Underwater Acoustic Sensor Networks
Get PDFWith the growing use of underwater acoustic communications (UWAC) for both industrial and military operations, there is a need to ensure communication security. A particular challenge is represented by underwater acoustic networks (UWANs), which are often left unattended over long periods of time. Currently, due to physical and performance limitations, UWAC packets rarely include encryption, leaving the UWAN exposed to external attacks faking legitimate messages. In this paper, we propose a new algorithm for message authentication in a UWAN setting. We begin by observing that, due to the strong spatial dependency of the underwater acoustic channel, an attacker can attempt to mimic the channel associated with the legitimate transmitter only for a small set of receivers, typically just for a single one. Taking this into account, our scheme relies on trusted nodes that independently help a sink node in the authentication process. For each incoming packet, the sink fuses beliefs evaluated by the trusted nodes to reach an authentication decision. These beliefs are based on estimated statistical channel parameters, chosen to be the most sensitive to the transmitter-receiver displacement. Our simulation results show accurate identification of an attacker's packet. We also report results from a sea experiment demonstrating the effectiveness of our approach.pu
Adaptive Resource Provisioning based on Application State
Get PDFInfrastructure providers employing Virtual Network Functions (VNFs) in a cloud computing context need to find a balance between optimal resource utilization and adherence to agreed Service Level Agreements (SLAs). Tenants should be allocated as much computing, storage and network capacity as they need in order not to violate SLAs, but not more so that the infrastructure provider can accommodate more tenants to increase revenue. This paper presents an optimizer VNF that ensures that a given virtual machine (VM) is sufficiently utilized before directing traffic to another VM, and an orchestrator VNF that scales the number of VMs up or down as needed when workloads change, thereby limiting the number of active VMs to a minimum that can deliver the service. We setup a testbed to transcode and stream Video on Demand (VoD) as a service. We present experimental results which show that when the optimizer and orchestrator are used together they outperform static provisioning in terms of both resource utilization and service response times.TRUEpu
Towards Large-Scale and Collaborative Spectrum Monitoring Systems using IoT Devices
Get PDFThe Electromagnetic (EM) spectrum is well regulated by frequency assignment authorities, national regulatory agencies and the International Communication Union (ITU). Nowadays more and more devices such as mobile phones and Internet-of-Things (IoT) sensors make use of wireless communication. Additionally we need a more efficient use and a better understanding of the EM space to allocate and manage efficiently all communications. Governments and telecommunication operators perform spectrum measurements using expensive and bulky equipments scheduling very specific and limited spectrum campaigns. However, this approach does not scale as it can not allow to widely scan and analyze the spectrum 24/7 in real time due to the high cost of the large deployment. A pervasive deployment of spectrum sensors is required to solve this problem, allowing to monitor and analyze the EM radio waves in real time, across all possible frequencies, and physical locations.
This thesis presents ElectroSense, a crowdsourcing and collaborative system that enables large scale deployments using Internet-of-Things (IoT) spectrum sensors to collect EM spectrum data which is analyzed in a big data infrastructure. The ElectroSense platform seeks a more efficient, safe and reliable real-time monitoring of the EM space by improving the accessibility and the democratization of spectrum data for the scientific community, stakeholders and the general public. In this work, we first present the ElectroSense architecture, and the design challenges that must be faced to attract a large community of users and all potential stakeholders. It is envisioned that a large number of sensors deployed in ElectroSense will be at affordable cost, supported by more powerful spectrum sensors when possible. Although low-cost Radio Frequency (RF) sensors have an acceptable performance for measuring the EM spectrum, they present several drawbacks (e.g. frequency range, Analog-to-Digital Converter (ADC), maximum sampling rate, etc.) that can negatively affect the quality of collected spectrum data as well as the applications of interest for the community.
In order to counteract the above-mentioned limitations, we propose to exploit the fact that a dense network of spectrum sensors will be in range of the same transmitter(s). We envision to exploit this idea to enable smart collaborative algorithms among IoT RF sensors. In this thesis we identify the main research challenges to enable smart collaborative algorithms among low-cost RF sensors. We explore different crowdsourcing and collaborative scenarios where low-cost spectrum sensors work together in a distributed manner. First, we propose a fast and precise frequency offset estimation method for low-cost spectrum receivers that makes use of Long Term Evolution (LTE) signals broadcasted by the base stations. Second, we propose a novel, fast and precise Time-of-Arrival (ToA) estimation method for aircraft signals using low-cost IoT spectrum sensors that can achieve sub-nanosecond precision. Third, we propose a collaborative time division approach among sensors for sensing the spectrum in order to reduce the network uplink bandwidth for each spectrum sensor. By last, we present a methodology to enable the signal reconstruction in the backend. By multiplexing in frequency a certain number of non-coherent low-cost spectrum sensors, we are able to cover a signal bandwidth that would not otherwise be possible using a single receiver.
At the time of writing we are the first looking at the problem of collaborative signal reconstruction and decoding using In-phase & Quadrature (I/Q) data received from low-cost RF sensors. Our results reported in this thesis and obtained from the experiments made in real scenarios, suggest that it is feasible to enable collaborative spectrum monitoring strategies and signal decoding using commodity hardware as RF sensing sensors.Telematics EngineeringUniversidad Carlos III de Madrid, Spainpu
Demo: Video Transmission Using Low-Cost Visible Light Communication
Get PDFIn this paper we document the demo of the latest version
of OpenVLC, a low-cost platform for communicating using
Visible Light, and we prove we can transmit video with it.
This paper shows the setup used, the behavior of each of its
components, and the results expected. This is the !rst time
video transmission has been possible with OpenVLC and to
the best of our knowledge, the !rst time it has been done
with low-cost components.TRUEpu
High Fidelity Simulation of IEEE 802.11ad in ns-3 Using a Quasi-deterministic Channel Model
Get PDFSupporting high data-rates and a large number of connected devices has always been challenging for wireless technologies operating in the microwave band. Wireless communication in the millimeter band is a promising solution to address this challenge and deliver gigabit throughput and very low latency. However, efficient communication in this band poses a great challenge in terms of radio resource allocation and requires adequate network planning and efficient design of wireless networking protocols. Despite the availability of commercial devices utilizing the IEEE 802.11ad protocol, these devices provide only limited access to the operations of the lower layers of the protocol stack, which hinders in-depth analysis and development of innovative solutions. For these reasons, researchers rely on high-fidelity system-level simulators to understand the interactions and behavior of millimeter-wave communication devices. In this paper, we demonstrate the capabilities of the IEEE 802.11ad model in ns-3. This model allows researchers to study the performance of the IEEE 802.11ad protocol for various deployment settings with high fidelity, using realistic phased antenna arrays and quasi-deterministic channel models. More particularly, we look at the impact of LOS blockage and the use of NLOS paths on link performance. In addition, we show the benefits of deploying multiple access points per room to guarantee gigabit throughput per user. Finally, we evaluate the performance of the IEEE 802.11ad protocol in a typical high-density scenario consisting of a single access point and ten stations.TRUEpu
A System for Profiling the IXPs in a Region and Monitoring their Growth: Spotlight at the Internet Frontier
Get PDFThis work aims at designing and implementing a system able to profile and help manage the set of IXPs in an Internet region. As part of the Internet Society’s strategy to help monitor and understand the evolution of IXPs in a particular region, a route-collector data analyzer tool was developed before being deployed and tested in AfriNIC. In fact, traffic localization efforts in the African peering ecosystem would be more sustained and their efficacy assessed if they were supported by a platform, which evaluates and reports in real-time about their impact on the Internet. We thus built the “African” Route-collectors Data Analyzer (ARDA), an open source web platform for analyzing publicly available routing information collected since 2005 by local route-collectors. ARDA evaluates pre-defined metrics that picture the status of the interconnection at local, national, and regional levels. It shows that a small proportion of AfriNIC ASes (roughly 17 %) are peering in the region. Through them, 58% of all African networks are visible at one IXP or more. These have been static from April to September 2017, and even February 2018, underlining the need for increased efforts to improve local interconnectivity. We show how ARDA can help detect the impact of policies on the growth of local IXPs, or continually provide the community with up-to-date empirical data on the evolution of the IXP substrate. Given its features, this tool will be a helpful compass for stakeholders in the quest for better traffic localization and new interconnection opportunities in the targeted
region.pu
Highlights of SIGCOMM 2018
No full textThe Association for Computing Machinery’s Special Interest Group on Data Communication (ACM SIGCOMM) is a leading venue for research in architectures, protocols, technologies, and applications of computer networking and data communication. The ACM SIGCOMM annual conference spans all aspects of networks and networked systems, including packet processing, hardware and software, virtualization, routing, mobility, sensors, energy consumption, novel applications of artificial intelligence to networking, and usability of underlying communication technologies. Its participants include distinguished academics, brilliant students, and representatives of major multinational companies. Centered on its highly selective main conference, SIGCOMM published many landmark works in networking and communications. The conference also involves workshops, tutorials, presentation of demos, posters, industrial demos, student research competition, topic previews, and mentoring sessions. SIGCOMM 2018 met in Budapest on August 20-25. The first visit of ACM SIGCOMM to Eastern Europe became an unqualified success. Encompassing a variety of traditional and newly introduced events, the six-day conference program attracted around 750 attendees overall, with about 700 people registered for the 3-day main conference. This talk reviews the technical main-conference program, highlighting interesting ideas in its papers and identifying emerging research trends.FALSEpu
